ui/surface/transport_dib_mac.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/surface/transport_dib.h"
   6
   7 #include <sys/stat.h>
   8 #include <unistd.h>
   9
  10 #include "base/logging.h"
  11 #include "base/posix/eintr_wrapper.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/shared_memory.h"
  14 #include "skia/ext/platform_canvas.h"
  15
  16 TransportDIB::TransportDIB()
  17     : size_(0) {
  18 }
  19
  20 TransportDIB::TransportDIB(TransportDIB::Handle dib)
  21     : shared_memory_(dib, false /* read write */),
  22       size_(0) {
  23 }
  24
  25 TransportDIB::~TransportDIB() {
  26 }
  27
  28 // static
  29 TransportDIB* TransportDIB::Create(size_t size, uint32 sequence_num) {
  30   TransportDIB* dib = new TransportDIB;
  31   if (!dib->shared_memory_.CreateAndMapAnonymous(size)) {
  32     delete dib;
  33     return NULL;
  34   }
  35
  36   dib->size_ = size;
  37   return dib;
  38 }
  39
  40 // static
  41 TransportDIB* TransportDIB::Map(Handle handle) {
  42   scoped_ptr<TransportDIB> dib(CreateWithHandle(handle));
  43   if (!dib->Map())
  44     return NULL;
  45   return dib.release();
  46 }
  47
  48 // static
  49 TransportDIB* TransportDIB::CreateWithHandle(Handle handle) {
  50   return new TransportDIB(handle);
  51 }
  52
  53 // static
  54 bool TransportDIB::is_valid_handle(Handle dib) {
  55   return dib.fd >= 0;
  56 }
  57
  58 // static
  59 bool TransportDIB::is_valid_id(Id id) {
  60   return id != 0;
  61 }
  62
  63 skia::PlatformCanvas* TransportDIB::GetPlatformCanvas(int w, int h) {
  64   if (!memory() && !Map())
  65     return NULL;
  66   return skia::CreatePlatformCanvas(w, h, true,
  67                                     reinterpret_cast<uint8_t*>(memory()),
  68                                     skia::RETURN_NULL_ON_FAILURE);
  69 }
  70
  71 bool TransportDIB::Map() {
  72   if (!is_valid_handle(handle()))
  73     return false;
  74   if (memory())
  75     return true;
  76
  77   struct stat st;
  78   if ((fstat(shared_memory_.handle().fd, &st) != 0) ||
  79       (!shared_memory_.Map(st.st_size))) {
  80     return false;
  81   }
  82
  83   size_ = st.st_size;
  84   return true;
  85 }
  86
  87 void* TransportDIB::memory() const {
  88   return shared_memory_.memory();
  89 }
  90
  91 TransportDIB::Id TransportDIB::id() const {
  92   return shared_memory_.id();
  93 }
  94
  95 TransportDIB::Handle TransportDIB::handle() const {
  96   return shared_memory_.handle();
  97 }